"Hopper is a Realist." Life 2 (May 3, 1937), p. 46, ill. (color), calls it "Light House at Two Lights" and notes that it was painted in Cape Elizabeth, Maine.

"A Portfolio of Prize Paintings." Fortune (December 1937), p. 137.

Peyton Boswell, Jr. Modern American Painting. New York, 1939, pp. 159, 205, ill. p. 125 (color), calls it "Light House at Two Lights" and notes that the owner, Mrs. Samuel A. Tucker, has received so many requests to loan the work that it is "like having a very pretty debutante daughter. It is never at home.".

Edward Hopper. New York, 1945, unpaginated, ill.

"Ten Years of American Art: LIFE Reviews the Record of a Lively, Important Decade." Life 21 (November 25, 1946), ill. p. 74 (color).

Suzanne Burrey. "Edward Hopper: The Emptying Spaces." Arts Digest 29 (April 1, 1955), p. 8, notes the ubiquity of this work in reproduction and how it represents the artist's attraction to recurrent themes.

Royal Bailey Farnum. "The Stories Behind 8 Famous Paintings." Design 59 (March-April 1958), p. 174, ill., calls it "Lighthouse at Two Points"; notes that the feeling of isolation in this work is achieved by removing visual references to both people and the ocean.

Sanka Knox. "Moscow Fair Art To Be Seen Here: Whitney Museum to Show Controversial Collection of American Works." New York Times (July 22, 1959), ill. p. 29.

Sidney Bernard. "Edward Hopper, Poet-Painter of Loneliness." Literary Times (April 1965), p. 11, notes how the "lofty isolation" depicted in this work evokes "a theme of beginnings" like Robert Frost when he wrote "The land was ours before we were the land's".

"Hopper." Great Artists 4, no. 88 (1986), pp. 2792–93, ill. (color), mistakenly refers to it as a watercolor and notes that the painting's location, Cape Elizabeth, Maine, was known for its spectacular surf.

Deborah Lyons. "Record Books I, II, III, V." Edward Hopper: A Journal of His Work. New York, 1997, p. 30, artist notes this work was delivered to the Rehn Gallery in October 1929 and purchased by Mrs. Samuel A. Tucker around November 1, 1929 after seeing it in September.

''The people around here are up in arms,'' said John Rich Jr., a retired journalist whose front yard looks out on the vista in the Met's work and who, as a 10-year-old, saw Hopper painting it. Some residents are rueful partly because they are hobbled by their own laissez-faire attitude in the past. When the town council of Cape Elizabeth, a hamlet about 10 miles southeast of Portland, considered safeguarding historic buildings in recent years, it sided with private property rights over mandatory preservation. An ordinance passed last year simply requires anyone embarking on demolition or alteration of a landmark to give 45 days' notice to the town and to the Maine Historic Preservation Commission. ''That ties my hands,'' said Michael K. McGovern, the town manager.

On Thursday, about 40 citizens gathered at the town hall and decided to act. Afterward, Thomas M. Egan, an insurance agent who is becoming a de facto leader, vowed, ''We'll do whatever we must do to stop him.'' The group sent a three-member delegation to plead the preservationists' case with Mr. Kourakas on Friday, but he was unmoved. ''He said there would be no change in his plans and no delay, which means there's going to be a fight,'' Mr. Rich said.

Mr. Kourakas, 43, the head of Morgan Stanley's high-yield capital markets group, has told neighbors that he is not the villain here. Over the years, the farmland surrounding the keeper's house was graded and turned into housing lots; the assistant keeper's house that figures in some paintings was destroyed, and the keeper's house was renovated and expanded somewhat. His plan, he argues, reverses some alterations, restores some gingerbread and puts part of the roof line back where it was in Hopper's days.

Mr. Kourakas's blueprints, however, also extend one side of the building by 12 feet, add 16 feet to another side, turn a three-bedroom house into a six-bedroom one and create a garage with a connecting walkway to the house. ''The scope is just untenable,'' Mr. Egan said.

Gail Levin, the author of eight books on Hopper, including his biography and catalogue raisonne, agreed. ''It's a shame he is altering this major historic landmark,'' she said of Mr. Kourakas.

To Hopper, she said, there was ''something quintessentially American'' about lighthouses, especially this one. ''He painted many lighthouses, but there's none he painted more than the lighthouse at Two Lights,'' she said.

Two Lights also marked something of a turning point in the artist's career. As Ms. Levin recounts in ''Edward Hopper: An Intimate Biography'' (Knopf, 1995/University of California Press, 1998), Hopper and his wife, Jo, discovered Two Lights in 1927. Hopper had just sold ''Two on the Aisle,'' which depicts a pair of elegant women in a near-empty theater (now in the Toledo Museum of Art), for $1,500, his highest price thus far. The couple used the money to buy their first car and set out from Nyack, N.Y., for Maine.

At Two Lights, he painted ''Lighthouse Hill,'' an oil owned by the Dallas Museum of Art,, and ''Captain Upton's House,'' an oil that now belongs to the actor Steve Martin. Hopper also painted watercolors and oils of other parts of the Coast Guard complex at Two Lights, and he returned in 1929 to paint the view that the Met purchased in 1962.

Since then, Ms. Levin said, ''legions of minor artists'' have drawn inspiration from Hopper's lighthouses. And Hopper, of course, went on to glory. ''His images have become part of the very grain and texture of American experience,'' wrote the critic Robert Hughes in his book ''American Visions'' (Knopf, 1997), ''and even today, 30 years after his death, it's all but impossible to see America without some refraction through them.''

Champions of Two Lights fear they have too little time to stop Mr. Kourakas, particularly because they learned of the problem only on July 22, they say, when The Portland Press Herald reported that the notification had been filed six days earlier. ''We're trying to mobilize public opinion to let people see what's at stake here, that this debate is much more than someone trying to block a neighbor's view,'' said Paul McDonald, a lawyer who lives near the lighthouse.

The Cape Elizabeth Historical Society is circulating a petition, and The Press Herald has written editorials opposing Mr. Kourakas's plans. Martha Deprez, the executive director of Greater Portland Landmarks, a nonprofit organization, said she returned from a two-week vacation on Monday to ''all sorts of messages'' seeking her help, which she plans to give.

In the meantime, Mr. Egan, Mr. Rich and others are calling Maine's senators and state legislators to request their aid, since both the lighthouse and the keeper's cottage are on the National Register of Historic Places.

Hopper fans and preservationists are hoping an emergency town council meeting scheduled for tonight will give them more time. Council members say they will try to impose a 45-day or 90-day moratorium on any work at Two Lights.

Correction: August 20, 1998, Thursday A photograph yesterday with an article about planned changes to the site of a lighthouse and keeper's cottage in Maine that was painted several times by Edward Hopper carried an incorrect credit. The photo, of Hopper's painting ''Lighthouse at Two Lights'' (1929), was from the Metropolitan Museum of Art. Correction: August 19, 1998, Wednesday An article on page E1 about plans to alter the keeper's cottage at a Maine lighthouse that was the subject of paintings by Edward Hopper misstates the structure's status with regard to the National Register of Historic Places. The Two Lights Lighthouse itself is listed; the cottage is not.